I think so, yes.
See here:
Also note that the rubber ring doesn't sit right in the centre of the tube:
Not lecturing you, mind you. When I saw your pic last night I wondered too: so much so that I took my adapter and tried it both ways in my Vauen Quixx—specially because that's one pipe in which the adapter doesn't seem to fit when I insert it in the "right" direction (i.e. rounded end towards mortise).
The rounded end goes towards the stummel because Vauen pipes are not drilled dead centre (and no, this is NOT a defect: it's by design):
View attachment 95394
thus, if you have the flat end forwards you might end up plugging the draught hole.